ABSTRACT Support is requested for a Keystone Symposia conference entitled Innate and Non-Classical Immune Cells in Cancer Immunotherapy, organized by Drs. Nicholas D. Huntington, Eric Vivier, Caroline Robert and Lewis L. Lanier. The conference will be held in Keystone, Colorado from March 24-28, 2019. Immunotherapy has revolutionized the treatment of many cancer types over the past five years. T cell checkpoint inhibitors have led the way and are the focus of most immunotherapy trials. However innate and non-classical T cells contribute extensively to the tumor infiltrate and significantly impact on the tumor immune response in both the tumor microenvironment and in circulation. This symposium aims to bring together academic and industry opinion leaders in the fields of innate immune cells, natural killer cells, tumor microenvironment, tumor immune suppression, novel immunotherapeutic strategies and clinical cancer immunotherapy to define the next wave of immunotherapy breakthroughs that reach beyond the current T cell checkpoints. The conference offers a unique opportunity for an audience of diverse immunology and cancer research backgrounds to come together and share cutting edge insights into cancer immunology and rational approaches for therapeutic intervention that could be used as be standalone therapy or in combination with T cell checkpoint therapies. A key aim is to bring together experts with complementary interest in cancer immunotherapy that would not normally be drawn to common symposia and foster new dynamic collaborations to advance our understanding of tumor immunity.